Speaker
Description
Recent analysis involving the measurement of the kinetic Sunyaev-Zel’dovich (kSZ) effect and the stacking of optically selected eROSITA clusters have indicated that AGN feedback may be more efficient in lower mass haloes than previously thought, highlighting the need for multiple, orthogonal, probes of large scale structure that trace to the distribution of baryonic matter at different halo masses, redshifts and radii. Historically, X-ray measurements have served as the highest quality traces of hot gas in galaxy clusters and, as such, can provide invaluable constraints on the impacts of AGN feedback in galaxy clusters. With the FLAMINGO suite of cosmological hydrodynamical simulations, we explore the use of X-ray auto-correlations and cross-correlations with cosmic-shear and the thermal Sunyaev-Zel’dovich (tSZ) effect as probes of large-scale structure. Specifically, we highlight the sensitivity of these predicted X-ray—X-ray, X-ray—cosmic-shear and X-ray—tSZ probes too changes in cosmological parameters and variations in AGN feedback efficiency.
We find, from like-for-like comparisons, that FLAMINGO is in qualitative agreement with the same ensemble of probes measured from the Dark Energy Survey year three cosmic shear data, Planck tSZ maps, ROSAT and eROSITA X-ray maps. Additionally, these measurements prefer a lower cluster gas fraction than predicted by the fiducial FLAMINGO model, which is calibrated to reproduce pre-eROSITA results, gas fractions of low-redshift X-ray-selected groups and clusters. In this analysis, we note that contamination from unresolved AGN is non-negligible. Moreover, for the FLAMINGO X-ray—X-ray auto-correlation and X-ray—cosmic-shear cross-correlations to agree with the cluster gas fractions inferred from either kSZ effect measurements or eROSITA galaxy clusters, we must allow for a greater level of AGN contamination than predicted by the FLAMINGO model. Contamination from unresolved AGN is a limiting factor in this analysis and must be examined further in future studies.
